Introduction:
The presence of HER-2 has been shown to be a prognostic factor in many kinds of cancers, but its role in head and neck squamous cell carcinoma (HNSCC) is not still defined. The purpose of the current study is to investigate the role of HER-2 in HNSCC and its correlation with various clinicopathologic parameters.

Materials and Methods:
Peripheral blood samples were obtained from 17 healthy volunteers and 69 patients with HNSCC before curative surgery. The HER-2 level was determined in each sample by sandwich ELISA. Statistical analysis was performed using an independent t-test, one-way ANOVA, and Mann-Whitney Test.Results:
Mean HER-2 serum levels in patients with HNSCC compared with healthy controls was not statistically significant (3.85ng/ml vs. 3.75ng/ml; P>0.05). The mean serum level of HER-2 was higher in patients with lymph node involvement, metastasis, invasion, tumor size ≥2 cm, and stage>1, although the differences were not statistically significant (P>0.05).Discussion:
Mean HER-2 serum levels in patients with tumor size T3 and higher were greater than those from patients in stage T1 and T2, a finding which may be translated into disease progression, growth and invasiveness.Conclusion:
In this study the mean HER-2 serum level in patients with HNSCC was found statistically insignificant compared with the healthy control group. The role of soluble HER-2 as a tumor marker is still controversial and needs further studies to clarify its clinical relevance for early detection or screening for HNSCC.